FWIW, I bought one of these XTPower batteries about a year or so ago for the same reason (convenient barrel instead of USB), and it completely failed after 6 months. It continued powering devices, but wouldn’t accept a charge, and I contacted the manufacturer. After a ton of run-around and persistence, the company wanted me to ship it across the country on my own dime just to see if it was defective. No thanks / never again. Your mileage may vary.